(+)‐N‐Formylnorglaucine Rotamers from Unonopsis stipitata Diels

(+)‐N‐formylnorglaucine ( 1 ), an aporphine alkaloid containing a formyl group linked to the heterocyclic nitrogen, was isolated from the leaves of Unonopsis stipitata, an Amazon medicinal plant. The chemical structure was characterized based on 1D‐ and 2D‐NMR spectroscopy and HR‐ESI‐MS. NMR spectra revealed that 1 is composed of two rotamers ( 1a and 1b ) in a ratio of approximately 2:1. In addition, the fragmentation behavior of 1 displayed an unusual fragmentation pattern compared to regular aporphine alkaloids. Thus, this compound is reported for the first time as a natural product in this study.     

Chemical constituents of Talauma arcabucoana (Magnoliaceae): their brine shrimp lethality and antimicrobial activity

A new aporphine alkaloid, (-)-arcabucoine [(6aR)-N-formyl-1,2-methylenedioxy-9,10-dimethoxy-5,6,6a,7-tetrahydro-4H-dibenzo[de,g]quinoline] 1 was isolated from the leaves of Talauma arcabucoana (Magnoliaceae), along with the known compounds (-)-erythro-saccharinic acid lactone 2 and (-)-shikimic acid 3. Furthermore, the known aporphine alkaloids (-)-dicentrine 4, (-)-nordicentrine 5 and dicentrinone 6 were isolated from the stem bark. The alkaloids 4 and 5 were found to be the most active compounds in a brine shrimp lethality assay. In addition, alkaloids 1, 4 and 5 showed moderate growth inhibition against Staphylococcus aureus and Candida albicans.     

Alkaloids of the epigeal part ofAconitum karakolicum

The dynamics of the accumulation of alkaloids in the epigeal part ofAconitum karakolicum according to vegetation periods has been studied. It has been established that the highest content of alkaloids is found in the early period. On separating the combined alkaloids, the aporphine alkaloid isoboldine has been isolated from this plant for the first time and a new base has been obtained — napelline N-oxide, the structure of which has been shown on the basis of the results of a study of spectral characteristics and direct transition to napelline.     

Establishment of a search library about benzylisoquinoline alkaloids based on selective separation on the binaphthyl column and standard analysis on C18 column

A search library about benzylisoquinoline alkaloids was established based on preparation of alkaloid fractions from Rhizoma coptidis, Cortex phellodendri, and Rhizoma corydalis. In this work, two alkaloid fractions from each herbal medicine were first prepared based on selective separation on the “click” binaphthyl column. And then these alkaloid fractions were analyzed on C18 column by liquid chromatography coupled with tandem mass spectrometry. Many structure‐related compounds were included in these alkaloids fractions, which led to easy separation and good MS response in further work. Therefore, a search library of 52 benzylisoquinoline alkaloids was established, which included eight aporphine, 19 tetrahydroprotoberberine, two protopine, two benzyltetrahydroisoquinoline, and 21 protoberberine alkaloids. The information of the search library contained compound names, structures, retention times, accurate masses, fragmentation pathways of benzylisoquionline alkaloids, and their sources from three herbal medicines. Using such a library, the alkaloids, especially those trace and unknown components in some herbal medicine could be accurately and quickly identified. In addition, the distribution of benzylisoquinoline alkaloids in the herbal medicines could be also summarized by searching the source samples in the library.     

Isoquinoline alkaloids from Asimina triloba

A new aporphine glycoside, (-)-anolobine-9-O-β-D-glucopyranoside was isolated from the twigs of pawpaw (Asimina triloba) along with 7 known alkaloids including five aporphine alkaloids (anolobine, nornuciferine, norushinsunine, liriodenine, and lysicamine), a proaporhine alkaloid (stepharine), and a tetrahydrobenzylisoquinoline alkaloid (coclaurine). Among these compounds, nornuciferine, lysicamine, stepharine, and coclaurine are reported for the first time from this plant. The structure of the new compound was elucidated by spectroscopic methods, including 1?D, 2?D NMR, and HRESI-MS. The absolute configuration of compounds 1, 2, 7 and 8 was determined by CD experiment.     

Alkaloids ofLiriodendron tulipifera

The alkaloids of the tulip treeLiriodendron tulipifera L., family Magnoliaceae, are considered. More then 20 alkaloids have been isolated during different vegetation periods from various organs of the plant growing in Uzbekistan, and these have been assigned to the aporphine alkaloids and their dehydro, oxo, and 7-hydroxy derivatives; only two alkaloids proved to be derivatives of proaphorphine and of tetrahydroberberine. On the basis of the results of a comparative study of the NMR spectra of aporphines unsubstituted in ring D and some chemical transformations, the structure and configuration of the (R)-3-hydroxy-1,2-dimethoxyaporphine have been proposed for the new alkaloid lirinine. The absolute configurations, possible biogenetic interconnections, and mutual transitions of the alkaloids ofL. tylipifera that are derivatives of aporphine, oxoaporphine, and dehydroaporphine are discussed. A summery table is given which includes 41 alkaloids found in this plant.Institute of the Chemistry of Plant Substances of the Uzbek SSR, Academy of Sciences, Tashkent. Tashkent Agricultural Institute. Translated from Khimiya Prirodnykh Soedenii, No. 5, pp. 628–638, September–October, 1987.     

Alkaloids of the epigeal part ofAconitum karakolicum

The dynamics of the accumulation of alkaloids in the epigeal part ofAconitum karakolicum according to vegetation periods has been studied. It has been established that the highest content of alkaloids is found in the early period. On separating the combined alkaloids, the aporphine alkaloid isoboldine has been isolated from this plant for the first time and a new base has been obtained — napelline N-oxide, the structure of which has been shown on the basis of the results of a study of spectral characteristics and direct transition to napelline.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 826–829, November–December, 1979.     

Über Alkaloide aus Laurelia novae-zelandiae A. CUNN. 5. Mitteilung über natürliche und synthetische Isochinolinderivate

From an extract of Laurelia novae-zelandiae A. CUNN . the aporphine alkaloids (?)-pukateine (I), (?)-pukateine methyl ether (II), (?)-roemerine (IV), (?)-mecambroline (V), (+)-boldine (VII), (+)-isoboldine (VIII), (+)-laurolitsine (IX), and the proaporphine alkaloid (+)-stepharine (X) were isolated. Compounds II and V were up to now not described as natural alkaloids. These and the alkaloids IV, VII, VIII, IX and X are new for L. novae-zelandiae.     

Alkaloidal variation in cissampelos capensis (Menispermaceae)

Cissampelos capensis, commonly known by the Afrikaans name "dawidjies" or "dawidjieswortel", is the most important and best known medicinal plant of the family Menispermaceae used by the Khoisan and other rural people in the western region of South Africa. The main alkaloids in the leaves, stems and rhizomes were isolated and identified. Several of the main compounds were previously found in species of the related genus Antizoma and this similarity indicates that the two genera are closely related if not congeneric. Bulbocapnine (an aporphine alkaloid), dicentrine (an aporphine alkaloid) and salutaridine (a morphinane alkaloid) were the main alkaloids in the leaves, while bulbocapnine, cissacapine, cycleanine and insularine (the last three are bisbenzyltetrahydro-isoquinoline alkaloids) are the major compounds in the stems. The rhizome contains mostly bisbenzyltetrahydroisoquinoline alkaloids, with 12-O-methylcurine, cissacapine and cycleanine as the main ones. Alkaloids appear to be quite variable within different plant parts and different provenances, as confirmed by the difference in alkaloid patterns between coastal and inland forms of Cissampelos capensis (the morphinane alkaloid salutaridine, for example, is the major leaf alkaloid along the coast but is practically absent from the inland form of the species). The variety of alkaloids identified may contribute to the medicinal value of this species. The data on alkaloidal variation in the species has potential value and practical applications in chemotaxonomy, toxicology and pharmacognosy.     

Alkaloids ofLiriodendron tulipifera

The alkaloids of the tulip treeLiriodendron tulipifera L., family Magnoliaceae, are considered. More then 20 alkaloids have been isolated during different vegetation periods from various organs of the plant growing in Uzbekistan, and these have been assigned to the aporphine alkaloids and their dehydro, oxo, and 7-hydroxy derivatives; only two alkaloids proved to be derivatives of proaphorphine and of tetrahydroberberine. On the basis of the results of a comparative study of the NMR spectra of aporphines unsubstituted in ring D and some chemical transformations, the structure and configuration of the (R)-3-hydroxy-1,2-dimethoxyaporphine have been proposed for the new alkaloid lirinine. The absolute configurations, possible biogenetic interconnections, and mutual transitions of the alkaloids ofL. tylipifera that are derivatives of aporphine, oxoaporphine, and dehydroaporphine are discussed. A summery table is given which includes 41 alkaloids found in this plant.     

Fremy's salt oxidation of some isoquinoline alkaloids. Biogenetic considerations

Fremy's salt oxidation of benzyl isoquinoline and aporphine alkaloids to isoquinolones and oxoaporphines is described. Aminium radicals are suggested to account for the observed results. Their possible involvement in alkaloid biosynthesis is considered.     

The synthesis of some derivatives of 4,5,6,6a,7,12-hexahydroisoquinolino [8,l -ab]carbazole

As part of a general project on the chemistry of alkaloid analogues, the synthesis of derivatives 5 , of 4,5,6,6a,7,12-hexahydroisoquinolino[8,l-ab]carbazole, which can be considered as ring D indole analogues of the aporphine skeleton, was investigated. Compounds of this type are of interest on two grounds. Firstly it is conceivable some may occur naturally; and secondly, they may display unusual pharmacological properties, since the side-chain configuration of the tryptophan residue is intermediate between that present in lysergic acid diethylamide and the yohimbine-reserpine type alkaloids.     

Electrospray tandem mass spectrometry for structural characterization of aporphine- benzylisoquinoline alkaloids

Electrospray mass spectrometry and tandem mass spectrometry techniques were utilized to elucidate the structures of ten aporphine-benzylisoquinoline alkaloids, consisting of monoether link between aporphine and benzyltetrahydroisoquinoline units, which were isolated and identified previously from a variety of Thalictrum sp. (Ranunculaceae family) based mainly on the UV, IR, CD, NMR, EI-MS, CI-MS, derivatization, and chemical degradation techniques. In this investigation, protonated molecules, [M+H]+ ions, for nine tertiary alkaloids, a molecular ion, [M+'] ion, for a quaternary alkaloid, and very intense doubly- protonated molecules, [M+2H]2+ ions (100% of relative abundance) in Q1 Scan MS spectra, and prominent as well as diagnostic product ions for structural information in the tandem MS/MS spectra were observed for all investigated alkaloids each in nanogram quantities. More than 10 microg quantities of each investigated alkaloid or other isoquinoline and aporphine analogs needed for the CI-MS, EI-MS and FAB-MS analysis from the previous studies.     

Identification and metabolite profiling of alkaloids in aerial parts of Papaver rhoeas by liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry

Papaver plants can produce diverse bioactive alkaloids. Papaver rhoeas Linnaeus (common poppy or corn poppy) is an annual flowering medicinal plant used for treating cough, sleep disorder, and as a sedative, pain reliever, and food. It contains various powerful alkaloids like rhoeadine, benzylisoquinoline, and proaporphine. To investigate and identify alkaloids in the aerial parts of P. rhoeas, samples were collected at different growth stages and analyzed using liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry. A liquid chromatography with mass spectrometry method was developed for the identification and metabolite profiling of alkaloids for P. rhoeas by comparing with Papaver somniferum. Eighteen alkaloids involved in benzylisoquinoline alkaloid biosynthesis were used to optimize the liquid chromatography gradient and mass spectrometry conditions. Fifty‐five alkaloids, including protoberberine, benzylisoquinoline, aporphine, benzophenanthridine, and rhoeadine‐type alkaloids, were identified authentically or tentatively by liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry in samples taken during various growth stages. Rhoeadine alkaloids were observed only in P. rhoeas samples, and codeine and morphine were tentatively identified in P. somniferum. The liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry method can be a powerful tool for the identification of diverse metabolites in the genus Papaver. These results may help understand the biosynthesis of alkaloids in P. rhoeas and evaluate the quality of this plant for possible medicinal applications.     

Sesquiterpenes and alkaloids from Lindera chunii and their inhibitory activities against HIV-1 integrase

Three new eudesmane type sesquiterpenoid lindenanolides E (1), F (2) and G (3), and two new aporphine alkaloid lindechunines A (18) and B (20) were isolated from roots of Lindera chunii MERR., together with seven known sesquiterpenes including a new naturally-occurring lindenanolide H (4) and eight known aporphine alkaloids. The structures of these compounds were determined by spectroscopic means. Of the isolated compounds, hernandonine (14), laurolistine (16), 7-oxohernangerine (17) and lindechunine A (18) showed significant anti-human immunodeficiency virus type 1 (HIV-1) integrase activity with IC(50) values of 16.3, 7.7, 18.2 and 21.1 microM, respectively. The major alkaloids presented in the roots of L. chunii were quantitatively analyzed by an HPLC method.     

Determination of Lotus Leaf Alkaloids by Solid Phase Extraction Combined with High Performance Liquid Chromatography with Diode Array and Tandem Mass Spectrometry Detection

Lotus (nelumbo) is a traditional Chinese medical herb, and alkaloids are responsible for its pharmaceutical activities. Therefore, a rapid, validated method to determine alkaloids in lotus leaves is useful for its quality control. The goal of this work was to develop and validate an analytical method for the identification and quantitation of the bioactive alkaloids of extracts from lotus leaf and classification of lotus germplasm based on alkaloid concentrations. Solid-phase extraction was used prior to high-performance liquid chromatography coupled with photodiode array detection at 272 nm and tandem electrospray ionization triple quadrupole mass spectrometry for analysis. Nuciferine and O-nornuciferine were the dominant compounds in lotus used for seed production and some used for flower production. However, anonaine, roemerine, and N-nornuciferine were abundant only in some lotus flowers. All the lotuses were classified into four groups by principal component analysis of alkaloid content: 10 flower and three seed lotuses characterized by high nuciferine and O-nornuciferine content; 12 flower lotuses with high N-nornuciferine, roemerine, and anonaine content; two flower lotuses with a relatively high content of all five alkaloids; and cultivars with a low alkaloid content and without dominant alkaloids.     

Datura stramonium hairy roots tropane alkaloid content as a response to changes in Gamborg’s B5 medium

Hairy roots are less susceptible to manipulation by changes in medium composition than callus and cell suspension cultures. However, when the individual components of the Gamborg’s B₅ medium were modified one by one, several of them modified the yield of root cultures. Nitrogen (N) source changes, the absence of phosphorus (P), calcium (Ca), and cobalt (Co), and the increase in the sucrose content of the medium increased the level of alkaloids inDatura stramonium hairy root cultures. The use of ammoniun as N source provoked the alkaloid excretion into the medium. The addition of different auxins inhibited the alkaloid accumulation, but the addition of abscisic acid (ABA) did not change the alkaloid content of the cultures. The use of MeJa increased the content of hyoscyamine to 100%.     

Seasonal variation in alkaloid composition and antiproliferative activity of <Emphasis Type="Italic">Stylophorum lasiocarpum</Emphasis> (Oliv.) Fedde

Stylophorum lasiocarpum (Oliv.) Fedde (Papaveraceae) belongs to traditional Chinese medicine herbs but there was minimal information on the content of alkaloids in this plant. Extracts from the aerial part and roots were examined by liquid chromatography with UV and mass spectrometric detection, with nineteen alkaloids identified. Changes in alkaloid content over the entire vegetation period of a one- and two-year old plant were studied. The protoberberine alkaloids, coptisine and stylopine, were found to be the main substances in extracts of the aerial part irrespective of the plant’s age and time of harvest. Variable amounts of protopine, sanguinarine, chelerythrine, chelirubine, macarpine, chelilutine and berberine were also recorded in the aerial part. The roots contained significantly larger quantities of all alkaloids than the aerial part with the levels of most alkaloids varying from May to October, peaking in the middle of the vegetation period. Coptisine was the dominant alkaloid in all samples. The antiproliferative activities of the root extract and of seven individual alkaloids were tested on A375 human malignant melanoma cells. The significant dose-dependent toxicity of the root extract was attributed largely to the quaternary benzo[c]phenanthridine alkaloids, macarpine and sanguinarine.     

The dynamics of the accumulation of the alkaloids of the genus Ungernia

Summary A study ofU. victoris, U. tadshicorum, andU. trisphaera with respect to the vegetation periods and growth sites has shown that the maximum accumulation of alkaloids takes place in the early vegetation period and that naturally dried leaves do not contain alkaloids. The alkaloid content also depends on the growth site.In the period of the vigorous development of the epigeal part, some alkaloids are possibly converted into one another (hippeastrine into lycorine, galanthamine into narwedine, and narwedine into galanthamine).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 60–64, January, 1971.     

The Alkaloid of Cananga Odorata (I), Isolation of A New Base,Ushinsunine N-Oxide

A new aporphine alkaloid was isolated from the stem bark of Cananga odorata Hook. f. et Thomson (Annonaceae). The structure of this alkaloid has been established as ushinsunine N-oxide (6aS, 7R) ( 1 ) on the basis of spectroscopic evidences and by chemical transformation.